# First reviewed change — reference source

This is deterministic tutorial source, not an AI result or a pre-generated CAD
artifact. Its expected dimensions are 60 × 40 × 6 mm; the expected solid volume
is 14,400 mm³. Actual results are verified only by running the checks in your
installed engineering runtime and inspecting the saved document.

1. Read `create_reference.FCMacro` before running it. It uses the installed native
   FreeCAD-compatible API and Python's standard library. It downloads nothing.
2. Preserve your existing projects. Execute the macro deliberately through the
   application's macro mechanism, not as an automatically executed attachment.
3. It creates `~/SynthCrew-Tutorial/ReferenceBox.FCStd` and an actual kernel-check
   receipt. It refuses to overwrite either output. Do not delete existing work
   merely to make a repeated run pass; choose a new disposable output folder.
4. Reopen the saved model and verify its dimensions, one valid solid and volume.
5. Follow https://synthcrew.io/docs/worked-example for a separate Agent candidate,
   Preview, explicit Apply and post-Apply validation. The macro itself does not
   test the app's candidate-promotion workflow and performs no inference.

If the native runtime is unavailable, record the checks as unverified. Syntax
checking this source or reading serialized metadata is not a geometry test.

Copyright 2026 SynthCrew. This small example source may be used, modified and
redistributed under the MIT license. Provided without warranty; independently
verify any engineering use. Upstream application licenses remain separate.

A prebuilt ReferenceBox.FCStd and verification.json are also provided. The receipt
records the actual deterministic Linux ARM64 1.1.4 kernel check, saved-file reopen
and source/artifact hashes. It is not an AI or Client installer qualification.